Microwave cooking, tempering, and pasteurizing of foods involves several complex interacting physical phenomena. Although such processes are widely used, the interactions between food product, packaging, microwave oven itself particularly complicated, not well understood, applicable simulation tools lacking. In this contribution we describe a combined finite difference time domain model for electromagnetic heat transfer which include temperature dependence electrical thermal properties...

Glucosinolates are phytochemicals with important health and nutritional benefits. This study reports the use of high-performance liquid chromatography (HPLC) mid-infrared (MIR) spectroscopy to characterise differentiate between broccoli varieties systems production (organic vs. non-organic) depending on their glucosinolate content infrared fingerprint. Broccoli samples (n = 53) from seven were analysed using MIR HPLC. Differences in spectra individual observed carbohydrate fingerprint region...

An idealised mesoscale model of the enzymatic digestion starch modelled as a polymer aggregate is used to study effect various enzyme properties, such efficiency, range and radius, on rate at which monomers are released from aggregate. Depending efficiency process found be either reaction- or diffusion-limited. Additionally proportional volume around each bond that accessible enzyme, determined by radius enzyme. Simulations uniformly mixed susceptible resistant polymers reveal no significant...

Industrial microwave food processing is universally based on single frequency sources. With the emergence of variable ovens, it possible to exploit dependence a food's permittivity and/or choice heating frequency, for example as new route achieving targeted heating. Variable procedures are developed overcome geometry roughly spherical foodstuff dominating pattern when heated in fi xed applicators. Target mean temperatures 55, 75 and 90°C within 2 minutes without physical damage were set;...

Summary Glucosinolates (GSLs), compounds with potential chemo‐preventative properties, can be affected by pre‐ and post‐harvest processes. Therefore, monitoring their content is important for the food agricultural industries. This study evaluates application of mid‐infrared (MIR) spectroscopy determination GSLs in commercial broccoli ( Brassica oleracea var. italica ). Broccoli n = 53) from different varieties were analysed using MIR high‐performance liquid chromatography to develop partial...

Summary Food processors are increasingly looking towards new microwave‐based technologies to deliver competitive advantage in the market place, reduce operational costs, allow greater product innovation and increase flexibility without need for large capital investments. The technical barriers widespread exploitation of microwave heating, opportunities heating food processing, discussed context understand field/material/process interaction. It is shown how a application interference...

The aim was to incorporate vegetables containing the phytochemicals quercetin, apigenin, glucoraphanin and carotenoids into a processed potato-based snack assess their bioaccessibility bioavailability. Three different processing routes were tested for incorporation retention of in snacks using individually quick frozen or freeze-dried vegetables. No significant differences uptake transport quercetin apigenin between vegetable mix observed CaCo-2 transwell model. Simulated vitro digestions...

Abstract Magnetic Resonance Imaging (MRI) has been used to map in three dimensions, non-invasively, the complex heating patterns induced by microwave heating. Comparisons with infra-red thermal imaging of surface are demonstrated. The effects differential properties have characterized for a model food sample. potential applications MRI temperature mapping optimizing domestic and industrial use microwaves foods is discussed.

Product development of microwavable foods originally suffered from a high degree non-uniform heating which is generic in microwave heating. Typically, have either overheated edges or under heated centres. This was compounded by short reheat times allowed little opportunity for temperature equilibration. A crucial step overcoming this problem has been the understanding provided time-temperature data. Conventional measurements thermocouple, etc. are inappropriate cooking due to electric fields...

Abstract In this work, a multi-resonant metasurface that can be tailored to absorb microwaves at one or more frequencies is explored. Surface shapes based on an ‘anchor’ motif, incorporating hexagonal, square and triangular-shaped resonant elements, are shown readily tailorable provide targeted range of microwave responses. A consisting etched copper layer, spaced above ground plane by thin (< 1/10th wavelength) low-loss dielectric experimentally characterised. The fundamental resonances...

Sulforaphane-rich extract was prepared from broccoli. The encapsulated with whey and pea protein isolates by freeze-drying. products were characterised assessed for in vitro bioaccessibility bioavailability.

Abstract The microwave-heating behaviours observed in many food-stuffs are often complex and apparently unpredictable. To identify the underlying factors which give rise to this complexity, a novel means of classifying predicting behaviour is proposed validated. approach based on applicator type, material-electrical size (related physical electrical properties) how microwave field controlled. It shown classification method can provide useful framework for understanding principal heating...

Microbiological assurance protocols for food preservation are based on the ‘worst‐case’ slowest heating point within product. For conduction‐limited processing, this leads to well‐known overheating near surface regions of products, with resultant quality loss. volumetric processes such as microwave heating, it is practically impossible guarantee where will be. Consequently, regimes generally excessive and product often similar conventional processes. It well known that Magnetic Resonance...

The effective porosity is an important quantitative parameter for food products that has a significant effect on taste and quality. It challenging to quantify the apparent of fried potato crisps as they have thin irregularly shaped cross section containing oil water. This study uses novel micro-CT technique determine solid volume fraction hence three types crisps: standard continuously crisps, microwaved 'kettle' crisps.It was found kettle had lowest at 0.54, providing desired crunchy lower...

The rapid rise in microwave oven ownership the mid-1980s has led to a new application of thermal imaging – food industry. Food companies have become increasingly aware that very heating afforded by ovens can affect final eating quality food. Thermal is seen as powerful tool quantify temperature distribution within foods and thus provide way designing specifically be micro-waved.

Phytochemicals are bioactive compounds widely recognised for their potential to help in disease prevention, without being classified as essential nutrients. They therefore contribute the functional food landscape - that provides additional health benefits beyond its basic nutrition. Though impact of various drying techniques on phytochemicals has been extensively studied, there is limited research when applied composite snack foods. This study investigated influence vegetable pre-processing...

Summary The effects of food component layout and packaging materials (foil vs . plastic) on the microwave reheating characteristics a standard experimental frozen ready meal consisting ground beef (130g), processed peas (80g) mashed potato (102g) were studied. results show that foil trays can be used successfully to achieve even heating, for best heating rates components need matched. This achieved by shielding beef, so reducing rate two vegetable components. thawing times, after times 72°C...